Introduction: Bell pepper (Capsicum annuum L.) is an important plant of belong to family Solanaceae with the origin of Mexico, which is a rich source of vitamins and beneficial antioxidants to the health and the immune system. The green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the severe important pests of bell pepper in the greenhouse, which cause damage in both direct and indirect by feeding on sap and transmitting of viral diseases. The use of insecticides is the most commonly used method for controlling M. persicae, but in addition to the environmental contaminating, it increased the aphid resistance to chemical pesticides. Biological control is one of the alternative methods compatible with the crop ecosystems and is an important component in integrated pest management programs. The aphidophagous midge, Aphidoletes aphidimyza Rondani is an appropriative and important predator of various species aphids including M. persicae. Also, the quality of host plants on the first level of nutrition have important effect on the eco- physiology characteristics of the predator on the third level of nutrition. In this study, the effect of foliar application of micronutrient fertilizers of iron, zinc, copper and manganese on bell pepper was investigated on the biological and demographic parameters of A. aphidimyza fed on M. persicae in greenhouse conditions. Materials and Methods: The experiments were done as a completely randomized design with 50 replications per treatments during 2020-2021 in the greenhouse. The foliar application of micronutrient was carried out in four-to six-leaf stages with a certain amount of each fertilizer. At the beginning of the experiment, 100 eggs were considered to investigate the study of biology and the life table parameters of A. aphidimyza reared on the M. persicae fed on in each of the experimental treatments. Then daily, these eggs on the all treatments were monitored for recording incubation duration, survival rate and larval developmental duration (50 larvae). A mixture of aphids of different stages were Placed daily on each leaves treatment to feed of A. aphidimyza. Then, the experiments and the observations continued until the emergence of adult insects. After, a pair of male and female adult insects (15 pairs per treatment) were released into each experimental container containing leaves aphid infestation. Daily, the investigate continued for recording of pre-oviposition and oviposition duration, fecundity, male and female longevity until the death of the last individual. Recording of life table parameters and data analysis was performed using the bisexual life table method in TWOSEX-MSChart software. The results were accomplished by Tukey’s post hoc Honestly Significant Difference (HSD) test for showing the mean comparisons (Mean±SE). Results and Discussion: Based on results, the highest and lowest the intrinsic rate of increase (0.148 and 0.097 / day), the finite rate of population increase (1.160, 1.102 per day) and the net reproduction rate (15.8, and 6.42 offspring/individual) of A. aphidimyza were observed on iron and control treatments, respectively. The results show that there was a significant difference between the different treatments in terms of mean generation time (T) and the highest and the lowest T was obtained on control (19.003 day) and manganese treatment (18.096 day), respectively. Also, the foliar application of micronutrient fertilizers led to reduce the pre-adult time and increase, fecundity, oviposition period and the male and female longevity of A. aphidimyza. The results of this study show that the foliar application of plants with micronutrient fertilizers by improving the growth quality and inducing antibiotic resistance in host plants, has a positive effect on the biology and life table of A. aphidimyza. Conclusion: The host plants, as the first level of nutrition, have important effects on the predator biology as the third level of nutrition. So, the use of micronutrients by improving the quality of host plants herbivorous insects can be affect the different aspects of the biological characteristics of the higher nutrient level in plant-herbivorous interactions. Therefore, the foliar application of bell pepper with micronutrient fertilizers along with the use of A. aphidimyza as an appropriative biological control agent for aphids can be effective in integrated management programs of M. persicae.
شبپره مینوز گوجهفرنگی یکی از آفات جدید و مهم گوجهفرنگی در ایران است و هر ساله باعث کاهش راندمان و کیفیت محصول از نظر بازارپسندی می‌گردد. جهت معرفی حشرهکشهای جدید و مؤثر برای کنترل این آفت، این آزمایش در قالب طرح بلوک‌های کامل تصادفی با شش تیمار و سه تکرار در مزارع گوجه فرنگی سه استان کرمانشاه، مرکزی و هرمزگان در سال 1399 انجام شد. تیمارهای آزمایش شامل حشرهکشهای تترانیلیپرول SC 200 با دو غلظت 250 و 350 میلیلیتر در هکتار، ایندوکساکارب EC 15% به‌مقدار 250 میلیلیتر در هکتار، فلوبن دیامید WG20% به‌میزان 250 گرم در هکتار، لوفنرون+ امامکتین بنزوات WG 50% معادل 100 گرم در هکتار بودند. نتایج نشان داد که در روز چهاردهم پس از سم‌پاشی، حشرهکش تترانیلی پرول 350 میلیلیتر در هکتار با 03/72 درصد کارایی در استان مرکزی ، با 74/82، درصد کارایی در استان کرمانشاه و 17/82 درصد کارایی در استان هرمزگان از تاثیر بالاتری نسبت به سایر تیمارها برخوردار بوده است. بنابراین غلظت 350 میلیلیتر در هکتار حشرهکش تترانیلیپرول برای کنترل لاروهای شبپره مینوز در مزارع گوجهفرنگی مؤثر بوده و قابل توصیه شدن است.
Introduction: One of the major pests of apple trees all-around of Iran is two-spotted spider mites (TSM, Tetranychus urticae Koch (1836)). This pest reported from Gorgan and Mazandaran areas for the first time. This cosmopolitan mite is reported in almost all parts of the country and found in all countries of the world on more than 150 economic plant species. This pest has been causing damage to the farmer in various apple orchards in the country every year. Because of high rate of fecundity, high population density, short life cycle and develop resistance to pesticides, TSM is an invasive pest on apple trees and difficult to control. Also, due to the continued use of various broad-spectrum chemical insecticides / Acaricides to controlling this pest, in addition to making the potential of resistance, it has also eliminated natural enemies. Up to date no botanical acaricides has been registered on TSM in apple orchards of Iran. Accordingly, Pestout® as a botanical acaricide to control the active stages of TSM at two concentrations and in comparison to spirodiclofen and fenazaquin were evaluated in three provinces of Tehran, Isfahan and Khorasan Razavi in 2018. Materials and Methods: During 2018, Pestout® contain cottonseed and clove oils as a botanical acaricide to control the active stages of TSM at concentrations of 3 and 5 ml/l and in comparison of spirodiclofen SC 24% (Envidor®) 0.5 ml/l, fenazaquin SC 20% (Pride®) 0.5 ml/l and control (spraying) were evaluated in three provinces of Tehran, Isfahan and Khorasan Razavi in 2018. The experiment was carried out in a randomized complete block design with three replications (each replicate containing two trees variety yellow with the same conditions) for each treatment. Sampling was taken 1 day before and after spraying, at 3, 7 and 14 days’ intervals from 40 leaves of each experimental unit. Then the immature and female adults of spider mites in the leaves were counted and registered by using binocular in Agricultural Zoology Research Laboratory of the Iranian research institute of plant protection and also in Isfahan and Khorasan Razavi provinces. Data obtained from sampling were corrected by Henderson-Tilton formula. The normality of the data was evaluated using SAS software and Kolmogorov-Smirnov test. After analysis of variance using one-way ANOVA in SAS software mean comparison was performed by Duncan’s multiple range test in SAS 9.4 software. Results and Discussion: The analysis of variance showed that there was a significant difference between all treatments with control in three provinces across all days. Based on the results obtained in Tehran province, both concentrations of Pestout (With more than 82% mortality) besides of Envidor (with more than 86% mortality) were most efficient in all days after spraying. In Isfahan province, the efficacy of Pestout in both concentrations were in the same group with Envidor and Pride. On the other hand, no significant differences were observed between the abovementioned treatments in all days. In fact, for all four treatments acceptable performance recorded. In this province, the mean mortality of 3 ml/l Pestout varied between 74% to 80% during the test days and for concentrations 5 ml/l were 77% to 82%. In Khorasan Razavi province, the efficacy of Pestout 5 ml/l on 3, 7 and 14 days after treatment were more than 92%, 94% and 89% mortality, respectively. Also, mean mortality at concentrations 3 ml/l were recorded 84.70%, 89.91% and 82.16%, respectively. Therefore, both concentrations in this province had a good efficacy. Conclusion: Poor orchard management and the effects of climate change, are increasing pest problems, including TSM incidence, in Iranian orchards. Increased chemical pesticide use is leading to greater occurrence of pest resistance, insufficient control and increased production costs are some of the problems. The registration and implementation of low risk and effective botanical pesticides are one of the best methods for solving the problem and make a great IPM program in the orchards. Therefore, in the present study, it can be concluded that Pestout is a good candidate for controlling the two-spotted spider mite on apple trees, and the concentration 3 ml/l of this compound is recommendable in Iran.
Introduction Sweet corn (Zea mays L. var. saccharata) is an important crop, grown over 2,000 hectares in Iran. The consumption demand for sweet corn in its fresh form or as a processed crop has contributed to a significant increase in its cultivation in recent years. Sweet corn is susceptible to weed competition for nutrients, moisture, and light interception. Herbicides labeled for use on sweet corn are limited. Chemical control can be very important because of the low efficiency and cost effectiveness of mechanical or other methods of weed control. Hence, it is necessary to provide information about the sulfonylurea herbicides and suitable doses. Sulfonylureas such as nicosulfuron, rimsulfuron, and foramsulfuron are effective group of herbicides for annual and perennial weed control in maize. These herbicides provide a new chance for weed management in maize. Their mode of action occurs through inhibiting acetolactate synthase (ALS), thereby interfering with the production of branched-chain amino acids, leucine, isoleucine, and valine. The objectives of this experiment were to evaluate the effect of different doses of sulfonylurea herbicides on weeds control and growth and yield of sweet corn. Materials and Methods In order to evaluate the effect of different doses of sulfonylurea herbicides on weeds control and growth and yield of sweet corn (KSC403su), a field study carried out during 2015 growing seasons at the Agricultural College of Shiraz University. The experiment was conducted in a randomized complete block design with 4 replications. Treatments included different doses of nicosulfuron (1.5, 2 and 2.5 l ha-1), foramsulfuron + idosulfuron (1, 1.5 and 2 l ha-1) and acetochlor (4.5, 5 and 5.5 l ha-1) herbicides and weed free and weedy control. The number and dry weight of aboveground weeds parts were harvested within three fixed 1 × 1 m quadrats in every plot, separated by species, enumerated, oven-dried at 75 °C for 48 h, and then weighed. Then, percent weed density and dry weight reductions were measured. The traits included ear length, ear diameter, ear number per plant, row number per ear, grain number per row, grain number per ear and canned grain yield. Data were analyzed using SAS v. 9.1 software (SAS Institute 2003). When significant differences were observed among treatments, mean comparisons were made using Duncan's multiple range tests (P < 0.05). Correlation coefficients between different traits were also calculated. Results and Discussion Results showed that the canned grain yield, 1000 grain weight and number of grain per ear were reduced by weeds up to 73, 33 and 60%, respectively. The highest dry weights reduction obtained were of redroot pigweed (Amaranthus retroflexus) (75.8 and 59.5%), lambsquarters (Chenopodium album) (49.84 and 38.76%), barnyard grass (Echinochloa crus-galli) (58.37 and 40.85%) and bindweed (Convolvulus arvensis) (60.56 and 55.06%), so that applying of nicosulfuron )2.5 l ha-1) and foramsulfuron + idosulfuron (2 l ha-1) herbicides caused reduction in total dry weight of weeds in comparison with weedy treatment, and canned seed yield increased by nicosulfuron )2.5 l ha-1) and foramsulfuron + idosulfuron (2 l ha-1) herbicides in comparison to the acetochlor. Acetochlor was the weakest treatment in the reduction of weed density and dry weight. The highest canned grain yield (8.00 and 7.03 t ha-1), number of row per ear (12.00 and 11.50), number of grain per row (25.00 and 24.75), number of grain per ear (299.00 and 285.50) and 1000 grain weight (325.06 and 308.44 g) were obtained in nicosulfuron )2.5 l ha-1) and foramsulfuron + idosulfuron (2 l ha-1) herbicides, respectively. Positive correlation was found between canned grain yield and 1000 grain weight (r = 0.83, p<0.05) and number of grain per ear (r = 0.96, p<0.05). Applying nicosulfuron showed a high efficiency as compared to the foramsulfuron + idosulfuron and acetochlor for weed suppression. Conclusion It can conclude that nicosulfuron at 2.5 l ha-1 showed the best performance for weed control, especially broadleaved weeds and were associated with the maximum sweet corn canned grain yield. Therefore, due to the restricted use of herbicide in sweet corn, the herbicide used in this experiment is not created serious injury in sweet corn at the recommended rate while effectively controlling weeds. Hence, utilization of this herbicide could be a favorable option in contemporary weed control programs for local or regional sweet corn growers. Acknowledgements We would like to thank the School of Agriculture, Shiraz University for their support, cooperation, and assistance throughout this research.
Introduction Plant development is defined as a series of phenological events that are controlled by external factors and determine changes in the shape or function of some organs. Temperature and photoperiod are two of the most important environmental factors affecting phenological development. Papaver rhoeas L. and Papaver dubium L., from the Papaveraceae family, are common annual winter weeds in northern Iran. The life cycle of these species is closely related to winter crops such as wheat (Triticum aestivum L.) and other winter cereals that compete severely with them. The Papaver species are capable of producing a huge amount of small-sized seeds that remain dormant at maturity. The timing of emergence, growth and sexual reproduction is highly important for the success of invasive weeds. Checking the phonological behavior of these plant species along with their seed production would be useful for decision-support systems helping managers select the best management strategies and, thereby, improving P. rhoeas and P. dubium control. Also, the phenology data would allow predicting these species invasibility of new areas. The present study was aimed to quantify the phonological behavior of these weeds. Materials and Methods In the present study, the phenology of P. rhoeas and P. dubium were studied in the research field at Agricultural Sciences and Natural Resources University of Sari, Iran, with an annual rainfall of 851 mm per year. Seeds of these species were collected from a wheat field located in Mazandaran province, north of Iran during spring 2018. These species seeds were cultivated on 12 November 2018. The phenological stages were recorded from emergence to the end of the seeding stage. The phenology was studied based on the growing degree day. At the end of the experiment, the period of each phenological stage was calculated based on the day and the growing degree day. In order to determine the morphological traits of the plant, eight sampling steps were performed. Morphological traits such as plant height, number of leaves, number of flowers, number of capsules, and dry matter were measured. Results and Discussion The results showed that P. rhoeas and P. dubium grow from 0 to 1723.56 and 1759.06 growth degrees day, respectively. During this period, seven phenological stages were recorded for these two species. These stages were included emergence, rosette (7-8 leaves), stem elongation and branching, blooming, flowering, fruiting, and seed maturity. The flowering stage period in both species was long, 48 days in P. dubium and 46 days in P. rhoeas. The results showed that the shortest and longest stages of development of these two weeds were emergence and stem elongation, respectively. In this study, the growth period of P. rhoeas and P. dubium took about eight months. It has some variation with regard to height, the number of flower, number of capsule and dry matter between both species under the same environmental conditions but both plants started their developmental stages at the same time and finished at almost the same rate. The trend of changes in height, number of leaves, number of flowers, number of capsules, and dry matter were similar in both species. The life cycle of these two species begins with germination in autumn and ends with seed production in late June. The longest period of growth stage in both species was in spring and this trend decreases in late spring. The flowering stage begins in late March and ends in mid-June. The maturity period of these two species was from mid-June to the end of the first decade of July. One of the characteristics of these two species is high seed production. In P. rhoeas, at the end of the fruiting stage, each plant produced an average of 13 capsules and each plant produced an average of 5000 seeds. Also, in P. dubium, each plant produced an average of 14 capsules, and each plant of this species produces an average of 5922 seeds. Conclusion Based on knowledge of the different phenological stages of the two species, it is possible to plan for proper management. From a managerial point of view, these two species should be controlled before the blooming stage; so that their seeds do not enter the seed bank, because their seeds are considered as causes of contamination in the field.
